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Starting with the bumpstick, Matt Summerfield at COMP Cams walked us through the new profiles that decrease the stress and wear on the lifters. These new profiles also require less valvespring seat pressure, which decreases stress on everything in the valvetrain. To visualize and simplify the difference in profiles, look at the old camshaft (left) that had lobes that were more rectangular in shape. This pushes the lifters sideways in their bores, literally squeezing them upward. The newer profile (right) has slightly more angle to the ramps, lowering the side-loading of the lifters. Naturally, this comes at the expense of duration, but the new profile minimizes the power loss of a "smaller" cam.